Wheelbase swivelling means



March 18, 1969 J BOLLER 3,432,910

WHEELBASE SWIVELLING MEANS Filed Oct. 7, 1965 Sheet of 5 K": v w l l 1 i "i L INVENTCR JOHN ABOLLER M I ATTORNEY March 18, 1969 J. A. BOLLER WHEELBASE SWIVELLING MEANS Sheet Filed Oct. 7, 1965 h K u INVENTOR JOHN A. BOLLER M TTORNEY March 18, 1969 J. A. BOLLER WHEELBASE SWIVELLING MEANS Sheet Filed Oct. 7, 1965 INVENTOR JOHN A. BOLLER BY' M ORN EY March 18, 1969 J. A. BOLLER WHEELBASE SWIVELLING MEANS Filed Oct. 7, 1965 Sheet WWW INVENTOR JOHN A BOLLER 74 fi A v TTORNEY March 18, 1969 .1. A. BOLLER WHEELBASE SWIVELLING MEANS Sheet Filed Oct. '7, 1965 LLLLU u L uiuumm uuuumxm rpmuuuun mulmmm jmu mu MLULUMH INVENTOR JOHN A. BOLLER BY TORNEY 7 Claims Int. Cl. B24b /00, 13/00, 13/02 ABSTRACT OF THE DISCLDSURE The apparatus of this disclosure is a cylindrical grinding machine having means for effecting relative transverse and longitudinal movements of a grinding wheel and work support. The grinding wheel support is mounted for swivelling movement so as to present the grinding wheel to the workpiece at an angle and to change the angle in response to a change in the direction of the relative longitudinal movement between the work and grinding wheel. The means for swivelling the wheel support consists of a cylinder mounted in fixed position on the wheel carriage. A pair of pistons in said cylinder are operable to shift the bracket and wheel support in either direction. By introducing fluid under pressure between the two pistons, the bracket and wheel support can be moved to an intermediate position. With the grinding wheel set at an angle in proper relation to the direction of the longitudinal movement, a heavy out can be taken on the workpiece and the grinding action distributed uniformly across the face of the grinding wheel.

This invention relates to grinding machines, particularly to machines generally used for traverse grinding.

It is an object of this invention to perform a traverse grinding operation with the grinding wheel at an angle to the workpiece so that the grinding action is distributed uniformly across the face of the grinding wheel.

Another object is to provide means for changing the angular relation between the grinding wheel and the work at each reversal of the traverse movement.

Another object is to provide a grinding wheel having a plurality of axially spaced grinding surfaces to permit a relatively low grinding pressure.

Another object is to provide a swivelling means arranged either to swivel the wheel support between two angular positions or to center the wheel support in an intermediate position.

Another object is to provide control means for shifting said swivelling means to said intermediate position.

In its preferred form, the invention consists of a more or less conventional plain cylindrical grinding machine having a wheel support mounted for swivelling so as to present the grinding wheel to the workpiece at an angle and to change the angle in response to a change in the direction of the relative traverse movement between the work and grinding wheel. By traversing the work and grinding wheel relative to one another with said grinding wheel set at an angle, a heavy cut can be taken and the grinding action distributed uniformly across the face of the grinding wheel.

The grinding wheel may be a single wide wheel with the operative face divided into axially spaced grinding surfaces or a plurality of similarly spaced, but separate grinding wheels. The purpose of this arrangement is to reduce the grinding force required to remove a given amount of the work.

The means for swivelling the wheel support consists of a cylinder having two independent pistons slidably mounted therein and arranged to move together in one direction or the other to swivel the wheel support and to move in opposite directions to locate said wheel support atent O in an intermediate position with the wheel axis parallel with the work axis.

FIG. 1 is a plan view of a cylindrical grinding machine showing the relative angular position of the wheel support and the work at each end of the traverse movement before said wheel support is swivelled for the beginning of the next traverse movement in the opposite direction.

FIG. 2 is a plan View of the wheel support showing the position of the swivelling means.

FIG. 3 is a left hand end view.

FIG. 4 is an enlarged sectional view of the swivelling means for the wheel support.

FIG. 5 is a hydraulic circuit for the swivelling means.

FIG. 6 is a partial plan view exaggerated to show the angular relation between the grinding wheel and workpiece and the distribution of the grinding action across the face of the grinding wheel.

FIG. 7 is an electric circuit.

Numeral 10 indicates the bed or base of a grinding machine, in this case, a roll grinder. Wheel carriage 11 is slidably mounted for longitudinal movement on bed 10. The means for effecting said longitudinal movement is similar to that disclosed in U.S. Patent 1,904,827, granted Apr. 18, 1933.

Wheel support 12 is slidably mounted on carriage 11 for movement transversely of said carriage toward and from workpiece W. Grinding wheel 13 is rotatably mounted on wheel support 12.

An intermediate slide member 15 between carriage 11 and wheel support 12 is mounted for swivelling about pivot 16.

Workpiece W is rotatably supported between headstock center 20 on headstock 21 and footstock center 22 on footstock 23.

The means for swivelling wheel support 12 about pivot 16 consists of a cylinder 30 mounted on carriage 11 adjacent slide member 15 by means of a bracket 30a.

Two axially spaced pistons 31 and 32 are slidably mounted in cylinder 30. The pistons are also slidably mounted on piston rod 33 having an intermediate collar 34 in abutting relation with each of pistons 31 and 32.

Plunger 35 is slidably mounted in one end of cylinder 30 in alignment with piston rod 33. Plunger 37 is slidably mounted in the other end 38 of cylinder 30 in alignment with piston rod 33.

Bracket 40 is attached to slide member 15 and has a loop portion 41 surrounding cylinder 30. Adjusting screws 42 and 43 are mounted in loop portion 41 in engagement with plungers 35 and 37 respectively.

Movement of either of pistons 31 and 32 is transmitted through collar 34, piston rod 33 and one or the other of plungers 35 and 37 to shift bracket 40 and slide member 15 and wheel support 12 about pivot 16. The extent of movement of bracket 40 and Wheel support 12 is determined by the setting of stop screws 50 and 51 in loop portion 41 of bracket 40.

Stop member 52 co-acting with stop screw 50 is mounted in cylinder end 36. Stop member 53 co-acting with stop screw 51 is mounted in cylinder end 38.

Stop screws 50 and 51 may be adjusted to change the zone and extent of movement of pistons 31 and 32 and wheel support 12. The zone of movement and the range must always be such that in each end position, there is always clearance between the pistons and the adjacent cylinder heads.

Operation During a grinding operation, the face of grinding wheel 13 is at an angle to workpiece W as shown in FIG. 6. Grinding wheel 13 may consist of several spaced elements, each of which removes a predetermined amount of stock from workpiece W. The spaced abrasive portions penetrate the workpiece W more effectively than a continuous abrasive surface of the same width.

Grinding wheel 13 is traversed the full length of workpiece W in this position. When grinding wheel 13 reaches the headstock end of the machine, limit switch 1LS closes to complete a circuit to energize control relay 7CR.

Contact 7CR1 closes in a circuit with selector switch 90 to energize swivel left relay 9CR.

Contact 9CR1 closes to hold relay 9CR energized.

Relay 7CR is deenergized by the release of limit switch 1LS when carriage 11 moves away from the headstock end of the machine.

Contact 9CR2 closes to energize solenoid 2, shifting valve 80 to the right and directing fluid under pressure from the pump to the right hand end of cylinder 30.

:Piston 32 is shifted to the left, against collar 34, carrying with it, piston rod 33 and piston 31. This movement is transmitted through piston rod 33 and plunger 35 to adjusting screw 42 in bracket 40 to swivel wheel support 12 to the left or counterclockwise. This movement is stopped when screw 51 engages the stop member 53. When bracket 40 and wheel support 12 are moved in the opposite direction, the movement is stopped when stop screw 50 in bracket 40 engages stop member 52.

With wheel support 12 and grinding wheel 13 in this position, carriage 11 moves toward the footstock end of the machine. When it reaches the end of the movement toward footstock 23, limit switch 2LS is closed to energize relay 6CR.

Contact 6CR1 in a circuit with selector switch 90, energizes swivel right relay SCR.

Contact 8CR1 closes to hold relay SCR energized after relay 6CR is deenergized by the release of limit switch 215.

Contact 8CR2 closes to energize swivel right solenoid 1, shifting valve 80' to the left and directing fluid under pressure from the pump to the left end of cylinder 30.

Piston 31 moves to the right, against collar 34, carrying with it, piston rod 33, piston 32 and plunger 37, to shift bracket 40 and wheel support 12 to the right or clockwise, to position grinding wheel 13 for the traverse movement toward headstock 21.

When it is desired to grind with the wheel face parallel with the surface of the workpiece, selector switch 90 is actuated to open the circuit to relays SCR and 9CR, and close the circuit to centering relay 10CR.

Contact 10CR1 completes a circuit to energize solenoid 3 to shift valve 85 to the right and direct fluid under pressure to the center of cylinder 30, shifting piston 31 to the left and piston 32 to the right. If said pistons are in the left hand position with plunger 37 extending into cylinder 30, piston 31 will move to the left a short distance to engage the cylinder end 36 and plunger 35. Piston 32 will move to the right to engage the cylinder end 38 and plunger 37, to shift bracket 40 and wheel support 12 to an intermediate position in which the face of grinding wheel 13 will be parallel with the surface of workpiece W. In centering wheel support 12, pistons 31 and 32 move to engage the respective cylinder ends and plungers. If wheel support 12 is off center to the left, piston 32 will act through plunger 37 and screw 43 to move bracket 40 and wheel support 12 to the right until screw .2 and plunger 35 are stopped by piston 31.

I claim: 1. In a grinding machine, (a) a base,

(b) a work support on said base,

() a carriage reciprocable longitudinally on said base,

(d) a grinding wheel support movable on said carriage toward and from said work support,

(e) a grinding wheel rotatably mounted on said wheel support,

(f) said wheel support movable angularly to either of two positions, in each of which the face of said grinding wheel is at an angle to a workpiece, whereby to distribute grinding action uniformly across the entire face of said grinding wheel,

(g) means operable at each end of the reciprocating movement of said carriage to effect said angular movement of said wheel support comprising (h) a cylinder attached to said carriage,

(i) a bracket on said wheel support having portions in operative relation to both ends of said cylinder,

(j) a pair of pistons in said cylinder,

(k) a piston rod on which said pistons are slidably mounted and an intermediate collar thereon through which each of said pistons acts,

(1) adjustable connections between said piston rod and said bracket including (m) a plunger in each end of said cylinder in line with said piston rod,

(n) adjusting screws in each portion of said bracket in co-acting relation with the adjacent plunger, (0) a reversing valve for directing fluid under pressure alternately to oposite ends of said cylinder,

(p) and means for introducing fluid under pressure between said pistons to shift said pistons in opposite directions, and said bracket and wheel support to an intermediate position, and to hold said wheel support firmly in said intermediate position.

2. In a machine tool (a) a movable member having a work engaging surface,

(b) means to move said movable member to either of two opposite positions for engaging a workpiece at either position comprising (c) a cylinder,

((1) a pair of pistons in said cylinder,

(e) connections between said pistons and said movable member,

(f) a reversing valve for directing fluid under pressure alternately to opposite ends of said cylinder,

(g) and means for introducing fluid under pressure at a point in said cylinder to shift said pistons in opposite directions and said movable member to an intermediate position, and to hold said movable member in said intermediate position.

3. In a machine tool,

(a) a work support,

(b) a tool support,

(0) one of said supports being mounted for longitudinal reciprocating movement relative to the other,

((1) said tool support being mounted for swivelling movement between predetermined limits to position said tool with its work engaging surface at either of two different positions angular to the surface of a workpiece,

(e) power means to effect said swivelling movement of said tool support,

(f) means operable at each end of said reciprocating movement to actuate said power means to change the angular position of said tool relative to said workpiece,

(g) and means operable selectively and independently of said reciprocating movement to actuate said power means and said tool support to an intermediate position.

4. In a grinding machine,

(a) a base,

(b) a work support on said base having means for rotating a workpiece,

(c) a carriage on said base,

(d) a grinding wheel support movable on said carriage toward and from said work support,

(e) a grinding wheel rotatably mounted on said wheel support,

(f) means for swivelling said wheel support between two opposite posit-ions,

(g) means for grinding said rotating workpiece substantially longer than the width of said grinding wheel comprising (h) means to effect relative longitudinal traversing movement between said supports with the face of said grinding wheel at an angle to the surface of said workpiece in accordance with the direction of said traversing movement,

(i) reversing means to change the direction of said traversing movement,

(j) and means operable when said traversing movement is reversed to actuate the means for swivelling said wheel support.

5. In a grinding machine,

(a) a base,

(b) a work support on said base having means for rotating a workpiece,

(c) a carriage on said base,

(d) a grinding wheel support movable on said carriage toward and from said work support,

(e) a grinding wheel rotatably mounted on said Wheel support,

(f) one of said supports being rec-iproca'ble longitudinally relative to the other for grinding workpieces substantially longer than the width of said grinding wheel,

(g) means to apply said grinding wheel with its peripheral face at an angle to the axis of said rotating workpiece including (h) means to swivel said wheel support between two opposite positions,

(i) and means operable at each end of said longitudinal movement to actuate said swivelling means to change the swivel position of said wheel support.

6. In a grinding machine,

(a) a base,

(b) a work support on said base,

(c) a carriage on said base,

(d) a grinding wheel support movable on said carriage toward and from said work support,

(e) a grinding wheel rotata-bly mounted on said wheel support,

( f) said wheel support being mounted for swivelling movement to place the face of said grinding wheel at either of two opposite positions angular to the surface of a workpiece,

(g) one of said supports being mounted for longitudinal reciprocating movement relative to the other,

(h) means to effect said swivelling movement of said wheel support comprising (i) a hydraulic motor mounted in operative relation to said wheel support,

(j) means operable at each end of said reciprocating movement to actuate said motor to swivel said wheel support from one of said opposite positions to the other,

(k) and means to actuate said motor to shift said wheel (b) a work support on said base,

(c) a carriage on said base,

(d) a grinding wheel support movable on said carriage toward and from said work support,

(e) a grinding wheel rotatably mounted on said wheel support,

(*f) said wheel support being mounted for swivelling movement to place the face of said grinding wheel at an angle to the surface of a workpiece,

30 (g) one of said supports being mounted for longitudinal reciprocating movement relative to the other,

(h) means to swivel said wheel support between two positions comprising (i) a motor mounted in operative relation to said wheel (j) means operable at each end of said reciprocating movement for actuating said motor to swivel said wheel support from one of said positions to the other,

(k) and means to actuate said motor to shift said wheel support from either of said positions to an intermediate position, and to hold said wheel support in said intermediate position.

References Cited UNITED STATES PATENTS 1,968,550 7/1934 Barnes 51-49 2,047,052 7/1936 Benzon 90-53 2,161,311 6/1939 Ott 51-49 m 2,543,661 2/1951 Edlich et al 90-53 X 3,146,648 9/1964 Ortet et a1 82-24 3,312,146 4/1964 Quere et al. 92-62 X FOREIGN PATENTS 4 674,805 10/ 1950 Great Britain.

ANDREW R. JUHASZ, Primary Examiner. G. WEIDENFELD, Assistant Examiner.

U.S. Cl.X.R. 90-53; 92-62, 

